Experiences of the intelligent road lighting Henri Juslén Philips Lighting Pentti Hautala SITO Oy Osmo Holmström Finnish Road Administration Mika Saari Philips Lighting Marjukka Eloholma Helsinki University of Technology Liisa Halonen Helsinki University of Technology

Why intelligent road lighting was installed System description User interface First year experiences Conclusions Future actions Content

Background Over the past few years road and street authorities have dimmed or switched of road lighting at random. Goal The main purpose of this control system is to save electricity and maintenance costs but without losses in traffic safety. From lighting point of view this means providing the optimum luminance level in relationship to the actual need. Why intelligent road lighting was installed?

Altogether 492 luminaires are controlled via the power line (PLC). The controlling method is voltage dimming by triac. The luminaires have their own addresses, and they recognize their own command from power line. Addresses are on components, which are in luminaires or columns. Lamp situation (on, off, dimming %, broken and blinking lamp, burning hours and connection failures) is sent to the Traffic Centre and to the maintenance company. System description

The luminance meter measures the luminance of the road surface.

Traffic monitoring system gives information about traffic situation. Sensors under the road surface System description

The weather station monitors weather conditions (road surface: wet, semi wet, dry, snowy). System description

Software, (developed by Edelcom Ltd and Doston Oy), calculates the correct dimming level for the luminaires and controls the luminaires automatically. System description

User interface

-In winter the switch-on and -off of the lamps occurred at the time of maximum traffic volumes -Control system has begun to decrease the power of the lamps immediately after the switch-on -During the times of low traffic at night the lamps have been burning at the minimum level First year experiences

Measured average daily power (% of the maximum) during Jan-Feb 2006 First year experiences

With this type of road lighting control system it is possible to achieve considerable savings in energy costs without decreasing the quality of road lighting. Considerable savings in energy use can be obtained especially by decreasing the road luminance level when the traffic volume is low. To get maximum benefit better optimization protocols are needed Conclusions

ValOT-project at HUT Lighting Laboratory The objective of the project is to develop the quality, safety and energy-efficiency of road lighting through development of intelligent road lighting control and operation of the control system in different traffic and weather conditions. The aim is to find basis and guidelines for the dynamic changing of the road lighting. In this Ring Road III information of the road surface weather conditions are used in the control of the road luminance level. In the ValOT-project luminance measurements on the road are made together with visibility measurements to study the choice of the luminance levels. With these measurements the effect of weather on visual conditions in driving will be investigated. Future actions

Experiences of the intelligent road lighting Henri Juslén Philips Lighting Pentti Hautala SITO Oy Osmo Holmström Finnish Road Administration Mika Saari Philips Lighting Marjukka Eloholma Helsinki University of Technology Liisa Halonen Helsinki University of Technology